Method of and apparatus for regulating the temperature of superheated steam.



D. S.'JACOBUS.

METHOD OF AND APPARATUS FOR REGULATING THE TEMPERATURE OF SUPERHEATED STEAMl APPLICATION FILED MAY24.1909.

1,149 265, Patented Aug, 10, 1915.

9 SHEETS-SHEET l- R I I WITNESSES: lIVI/EIVTOR //s ATTORNEYS D. S. JACOBUS.

METHOD OF AND APPARATUS FOR REGULATING THE TEMPERATURE OF SUPERHEATED STEAM.

' APPLICATION FlLED MAY 24, I909. 1 1 25 Patented Aug. 10, 1915.

9 SHEETS-SHEET 2.

WITNESSES IIVVENTOH a fi 291 B .SFJycoBuS ea/1, 4: 07

BY FM A05 ATTORNEYS D. S. JACOBUS. v I I METHOD OF AND APPARATUS FOR REGULATING THE TEMPERATURE OF SUPERHEATED STEAM.

APPLICATION FILED MAY24. 1909.

1,M9 265, Patented Aug. 10, 1915.

9 SHEETS-SHEET 3.

WITNESSES Zy ZJ S .73! cozn ZF-Q fimv; fzdW ATTORNEYS D. S. JACOBUS.

METHOD OF AND APPARATUS FOR REGULATING THE TEMPERATURE OF SUPERHEATED STEA APPLICATION FILED MAY 24. 1909.

LM965 Patented Aug. 10, 1915.

9 SHEETS-SHEET 4.

Z0 Q PM: 7 M By Ms man/v5 rs WITNESSES n. s. IACOBUS. METHOD OF AND APPARATUS FOR REGULATING THE TEMPERATURE OF SUPERHEATED STEAM.

' APPLICATION FILED MAY 24- I909. 1 149,265

Patented Aug. 10, 1915.

9 SHEETS-SHEET 6.

WITNESSES: lNI/E/VTUR I fl b 5. fies/Gus a M, 3y

W' /1710mm:

n. s JACOBUS.

METHOD OF AND APPARATUS FOR REGULATING THE TEMPERATURE OF SUPERHEAT ED STEAM.

APPLICATION FILED MAY 24.1909.

1,149,265., Patented Aug. 10,1915.

9 SHEETS-SHEET 7- W/T/VESSES: INVENTOR 'V 5 ATTORNEYS D. S. JACOBUS.

METHOD OF AND APPARATUS FOR REGULATING THE TEMPERATURE OF SUPERIHE-ATED STEAM. APPLICATION HLEYD MAY 24. 1909 Patented Aug. 10, 1915.-

9 SH EETS-SHEET 8.

INVE/VTUR DWI/0 WCOEQS WITNESSES. 71-4 f QR BY ATTORNEYS 1,149,265., A Patented Aug. 10, 1915.

D. S. JACOBUS. A

METHOD OF AND APPARATUS FOR REGULATING THE TEMPERATURE OF SUPERHEATED'STEAM. APPLICATION FILED MAY 24; 1909.

9 SHEETS-SHEET 9.

I EA.

WITNESSES. M/VENTUR f 24 5. @cofius 47 ATTORNEY! amazes.

@AVID S. JACOBUS, OF JERSEY CITY, NEW JERSEY, ASSIGNOR TO THE 'BABOOCK &

WILCOX COMPANY, OF BAYONNE, N JERSEY, A

CORPORATION OF NEW JERSEY.

METHOD OF AND APPARATUS FOR REG-ULATING THE TEMPERATURE OF SUPERHEATEE STEAM.

Application filed May 24,

following is a specification.

The successful development of the steam turbine, and' of reciprocating engines adapted to the use of superheated steam, has directed attention to methods of overcoming the troubles resulting from the excess of superheat. For the steam turbine the degree of superheat is seldom less than 100 F., and is usually higher, while the maximum superheat which may be used has yet to be determined. In a reciprocating engine the superheat which may be used to advantage is limited by the design ofthe working parts, and any considerable increase augments the difliculty of lubrication, and may cause trouble with the packings and the cracking of the cylinder. Owing to the presence of variables, such as. furnace con,- ditions and rate of flow of steam through the'superheatendt is impossible to maintain a substantially constant temperature of the superheated steam. I

The object of the present invention is to lestablish and maintain a practically constant temperature in superheated steam, where so desired, or atemperature which may be made to vary to meet certain conditions of service. This object of reducing the amount of fluctuation in the temperature of superheated steam to a degree which will prevent any danger from an, excess of superheat, is accomplished by placing in the path of the steam a thermostat which may be in the form of a closed vessel, which I have termed an evaporator, containing air or other gas, a volatile liquid, ora liquid which is not volatile at the temperature involved, or one depending upon unequal expansion of different metals, and utilizing the pressure generated in the evaporator by the heat of the superheated steam, or the expansion or contraction of the metals, to control the temperature of the steam.

According to the preferred method of practising my invention, I employ an evapo- Specification of Letters Patent.

Patented Aug. 10, 1915.

1909. Serial No. 498,012.

rator containing a volatile liquid such as water, alcohol or mercury, which may be placed in the path of the steam after its temperature has been reduced to a substantially constant figure whereby the governing action is secured by means of minute differences in the temperature of the steam which create correspondingly small differences of pressure in the evaporator. The principle involved is based upon the wellknown physical fact that in evaporating a volatile liqui'd there s a certain definite pressure corresponding to a given temperature. From this it follows that if the temperature of a volatile liquid in an evaporator is maintained at a certain fixed amount, the pressure of the vapor produced in the evaporator will remain constant.

In practising my preferred method I first modify the temperature of superheated steam of a varying initial temperature by subjecting it to the action of a cooling or heating medium so as. to bring the steam temperature to a predetermined constant figure, and after its temperature has been so modified causing the steam to come into contact with an evaporator containing a Volatile liquid, 'the temperature of such' liquid, and conseqeuntly the pressure of its vapor, remaining practically constant as long as thetemperatur of the steam re mains constant. Should, however, there be any variation of the temperature of the superheated steam in contact with the evaporator, such variation will produce a corresponding variation in the temperature of the volatile liquid and the pressure of its =vapor, .and this pressure is utilized by me to control the temperature of the steam.

The primary means of control, therefore, in practising my preferred method, consists of a closed evaporator containing a volatile V liquid which is acted on by the steam in 45 heater a to the controller.

prises two vertical sections gether steam fromthe controller-may be conveyed 'tio n partly in section of an attemperator and vevaporator showing their connection with each other and with a damper regulator. Figs. 3 to 8, inclusive, are enlarged detail views of parts of Fig. 2; Figs. 9 and 10 are enlarged detail views of the damper regulator of Fig. 2; Figs. 11, 12, and 13,

are elevations, partly in section, of modified forms of apparatus for practising my invention; Figs. 14 and 15 are elevations, partly in section, of modifications which utilize the unequal expansion of different metals to control the temperature of the steam; Fig. 16 is a sectional detail of Fig. 14.

Similar reference numerals indicate similar parts in the SGVGIfllVlGWS.

As above stated, I preferto use an evaporator'containing a volatile liquid to control the temperature of the superheated steam and I will first describe the various forms of apparatus in. whichsuch evaporator may be used. e

In Fig. 1 I h ve shown a boiler and engine plant for th: purpose of illustrating the adaptation thereto taining th temperature of the superheated steam delivered to the engine practically constant, and the relative location of my The plant com-- controller to the boiler. prises a boiler'A- having a superheater a; a feed water heater or economizer B, a controller. C for regulating the temperature of the superheated steam and an engine D adapted to utilize the steam. Although I have shownthe controller connected to a single boiler, it isto be understood that it may be connected to a bank of boilers and that the consists of a pipe 2. of suitable length in which is placed .a band of 'sheet metal 3 twisted throughout its length so as' to cause the superheated steam, whilezpassing through the pipe 2, to take a spiral path. In the lower part of the second section 4,

which is also of pipe, isa spirall twisted band 5 similar to theband 3. onnected to the upper part of section 4 is a steam outlet pipe 6 having at any convenient point therein a thermometer 7. Opening into the upper part of the attemperator is a water supply pipe 8 having a cock 9' by which the volume of water admitted to the attemperator may be controlled. On starting the apparatus, as more fully described hereafter,

of apparatus for mam:

the valve or cock 9 is opened to admit sufficient water to reduce the degree of superheat to the predetermined constant, and this constant is maintained by the following means.

In the'upper part of the section 4 of the controller is an evaporator 10 closed tov the steam and containing a volatile liquid such as water, alcohol or mercury, having a fixed boiling point for a given pressure. This evaporator 10 may be given any appropriate form which will insure a relatively large heating surface,-and a small internal volume. I have used a flattened sheet metal tube spirally twisted which gives the desired surface and at the same time spreads out the contained liquid, or causes it to come in contact with a large surface which aids or facilitates its evaporation and renders such liquid extremely sensitive to variations in the temperature of the surrounding steam.

- As shown, the evaporator is closed-at its upper end by welding in. a plug.11 adapted to receive one end of a pipe 12. The latter passes through a stufling box seated in a bushing 13 screwed into the T between the controller section 4 and the steam outlet pipe. 6 (Fig. 3). The pipe 12 leads to a regulatorw or governor of the Carmichael or Spencer type, such as is often usedfor regulating dampers in connection with boilers.

The regulator or governor, shown in detail in Figs. 9 and 10, comprises a chamber 14 having a flexible diaphraghm 15 which receives'at its under side through pipe 12 the pressure generated in the evaporator. Secured to the diaphragm is a stem '16 which projects through chamber 14 and bears against a lever 17 having its'fulcrum at 17. T 0 the outer end of lever 17 is fixed an auxiliary'lever 18, fulcrumed at 18, and

having a connecting rod 19 to a pilot valve 19. The force acting on the under side of the diaphragm 15 is opposed by the adjustable weight 17 and the removable weights 17 on lever 17 and the adjustable weight 18 on lever 18. By means of this system of levers the pilot valve is made to operate a piston 20' in cylinder 20 by water pressure. When the pressure generated in the evaporator increases. the levers 17 and 18 are raised, thus admitting water from the high pressure reservoir 21 to the under side of the piston, and to the upper side of the piston when the vapor pressure decreases. To

the piston is connected a power lever 22, the

free end of the latter being connected through turn-buckle 22 to a lever 23 which."

actuates the plug of the cock 9 inserted in the water supply pipe 8.

The forces operating the pilot valve are in pressure which are produced in the evaporator by the slight temperature variations in the steam surrounding the evaporator, and it'i's highly essential'that the movement of those corresponding to the slight differences the pilot valve be as free as possible. The piston which is operated by the water pressure provides an amount of force for moving the power lever 22 which is limited only by the size of the piston and the water pressure, so that the pilot valve which is operated by a comparatively minute'force may call into play-any amount of force required to operate the power lever. It is necessary that the power and range of motion shall be 'such that the lever 23 may either completely close the cock 9 or open it the required amount.

The action of the apparatus as a whole is to cause thepressure generated by the liquid on being evaporated in the evaporator 10 to act through the regulator in such manner that when there is any excess in the outgoing steam temperature, the variation in the pressure will cause the power lever 22 to rise and actuate the cock 9 so as to admit an additional quantity of water to the attemperator through the pipe 8 and thus reduce the temperature of ,the steam passing through the attemperator 2 to the predetermined normal or constant figure. On the other hand,

; should the temperature of the outgoing steam fall below the normal or constant figure the pressure of the evaporated liquid in the evaporator 10 will fall below the set figure and the machine will reduce the amount of water admitted to the attemperator through pipe 8 and thus prevent any lowering of the temperature below that at which the apparatus is set.

Before starting up the apparatus the turnbuckle 22 is adjusted so that the cock 9 will be fully open when the lever 22 is in its uppermost working position and closed when it is in its lowermost working position. After this" the turn-buckle 22 does-not require further adjustment 7 y In starting up the apparatus the weights 17 17 and 18 are so adjusted that the pressure produced by. the evaporation of the volatile liquid in the evaporator for the given constant temperature of superheat required will act on the diaphragm 15 to maintain the cock 9 in a position which will give the proper quantity of water to reduce the temperature of the steam to the required figure. After this the apparatus will automatically maintain the temperature at a substantially constant figure. In doing this the apparatus is governed by any slight change in the temperature of the steam leaving the attemperator. Should the steam temperature exceed the set figure, there will be a corresponding increase of pressure in the evaporator 10 which, acting on the diaphragm 15, will actuate the system of levers before described so as to open the cock 9 and permit a greater amount of water, according to the excess steam temperature, to flow through pipe 8 into the attemperator and The varying thus reduce'the temperature to substantially that of the set figure. 1

The water entering the attemperator 2 throughthe pipe 8 is made to mingle with the steam by the internal band 3 which is so formed as to cause its edges to assume a helical shape, and which rotates the steam and water passing through the attemperator so as to thoroughly sweep the surface and at the same time produce eddies which lead to a thorough mixture of the water with the superheated steam, the water, in fact, being vaporized and, according to the amount admitted and the latent heat imparted to the water together with the e'flect of the temperature of the water, reducing the temperature of the steam the desired amount. As

the temperature of the steam entering the l or close cock 9 so as to control the amount of water admitted to the attemperator. In this Way I have been able to preserve an approximately constant temperature of the outgoing superheated steam.-

0 give a concrete example, let it be assumed that the temperature of the superheated steam as it leaves the superheater a varies between 500 and 550 F. and that it is desired to deliver the steam to engine D at a substantially constant temperature of 500 F. which for 200 pounds steam pressure corresponds to 112 F. of superheat. initial steam temperatures would produce corresponding varying vapor pressures in the evaporator 10 and consequently varying pressures on the diaphragm 15 if the water supply to the throttling cock 9 were shut off and the attemperator portion of the apparatus then thrown out of action. By turning on the water by the cock 9 and adjusting the weights 17 17 and 18 the system of levers described will automatically adjust the cock 9 so that the volume of water admitted to the attemperator through pipe 8 will be sufiicient to reduce the degree of superheat to the predetermined amount which may be observed by thermometer. 7. After such adjustment any slight increase in the temperature of the steam surrounding the evaporator will cause a corresponding increase of vapor pressure in the evaporator and amovement of the power lever 22 to effect a further opening of cock 9 and the admission of a sufficiently greater volume of water to the attemperator to restore the steam temperature to that of the constant;

If, instead of reducing the temperature of the superheated steam to the lowest degree furnished by the superheater or a still lower amount, it is desired to limit the highest temperature that the steam attainson reaching the engine, this may be done by a proper adjustment of the weights. If in the above example the weights 17 17 and 18 are adjusted for a' temperature of 525 F. then the steam supplied to the engine Would vary in ',controlled by operating the cock 9 or by opening and closing a special valve in the manner above described. Also, instead of employing water as asupplemental source of energy to operate the piston 20 ,to move the power lever 22, steam, air or any other fluid may be used.

The apparatus above described illustrates one means for practising the preferred form of my invention, the-principle of which is the conversion of the temperature of superheated steam into pressure generated by a volatileliquid on being evaporated, and the employment of such pressure to regulate or control the temperature of the superheated steam. This principle may beapplied to an apparatus so constructed that the cooling water will circulate through coils instead of being injected into the superheated steam I by means such as illustrated in Fig. 11, in which the water pipe 8, instead of terminating in the upper part of the attemperator, is formed into a coil 24 inclosed in a chamber 25 through which the steam from super heater or is conveyed: The volume of water passin through coil 24 is controlled by cock 9 in" t e manner beforedescribed, that is to sa when the steam temperature surroun ing the evaporator 19 variesfrom the predetermined constant or set figure the volume of water admitted to the coil is corre spondingly varied through the movements of cock 9, which latter may be so adjusted as to be completely closed or opened to a greater 'orless extent to meet the requirements as to the degree of superheat. Instead of using cold water throughpipe 8 and coil 24, ,I may use oil or other heating medium heated to a temperature above that of the superheated steam, the object in such case beingto raise the temperature of the steam when it falls below a predetermined 30 degree of superheat. To effect this the adjustment of cock 9 will be made to correspond with a variation of steam temperature to .admit a sufficient volume of oil or other heating medium to coil 24 to raise the steam temperature to the degree desired, Whether that be the highest degree of superhe'at as the steam leaves the superheater a, or any degree between the limits of variation which may be determined upon as the desired constant. 4

In Fig. 12 I have shown another 'adapta tion of my invention which makes use of either a cold or a hot medium, or both, to establish andmaintain the desired degree of superheat. In this form the coil 24 is connected to a cold water supply pipe 8. In addition thereto I introduce into the pipe or chamber 25 a second coil connected to a pipe 27 through which oil or some other mediumheated to a temperature above that of the superheated steam or above any constant which it is desired to maintain, is conveyed. In the latter pipe is a cook 28. The parallel levers 29 and 29 connected respectively to the plugs of the cocks 9 and 28 are connected together by the rods 30,'one of which is connected to the power lever 22. The cocks are so adjusted that the movement of lever 22 will eiiect the opening of U one as the other closes. -,By this means, if the predetermined constant is within the limits of initial variation of the steam temperature the cock 9 will be opened to admit cold water to coil 24- to reduce the temperature to the constant, and cook 28will bev opened to admit hot oil or other heating medium to coil 26 to raise the temperature when it falls below the constant. The movement of lever 22 is efi'eoted by the same means heretofore described through variations of pressure generated in the evaporator 10 by any variation of the steam temperature surrounding the evaporator. By adjusting the Weightson the levers 17 and 18 the initial adjustment of the cooks 9 and 28 is efl'ected, this adjustment being varied.

only as the steam temperature surrounding the evaporator varies. v ()1 Q InFig. 13 I have shown another form of apparatus for accomplishing the desired results. In this form the cock 9 is actuated by a lever 31. connected to the rope of a Windlass 32, the latter being driven by an electric motor 33, in one direction to open the valve and in the opposite direction to close it according to/the temperature requirements. The forms of the attemperato-r and of the evaporator are substantially the same as shown in Fig. 2'and after the weight 34 has been once adjusted for the desired temperature of the superheated steam such temperature is maintained by the pressure generated in the evaporator 10 acting upon the diaphragm in chamber 14 to efiect a rotation of thedrum of the Windlass 32 in one direction or the other by the following means adjustable weight 34 and is adapted to be The lever 34 in this case carries an raised or lowered through the movement of the stem 16 attached to the flexible diacludes the two electroma-gnets 36 and 37 and the contacts 36 and 37 which contacts are.

insulated from the rest of the apparatus.

When the steam temperature exceeds the predetermined constant thereby increasing the pressure generated in the evaporator, le-

ver 34 will be raised and close circuit 35 through cont-act 36 thereby energizing magnet 36 and, when its armatures are attracted, closing the motor circuit 38 through the contacts 39 to rotate the motor in such a direction as to raise lever 31 and thereby open cock 9 an amount necessary to admit the necessary volume .of water to the attemperator to restore the steam temperature to the constant. On the other hand, should the temperature of the steam fall below the constant, the motor will be rotated in an opposite'direction by reason of lever 34 closing circuit 35 through contact 37 thereby energizing magnet 37 to close the motor circuit through the contacts 40. The closure of cock 9 may be complete or only partial as may be necessary under the conditions of steam temperature.

. feature the closed evaporator containing a.

' An excess of superheat of a few degrees above the constant is not productive of harmful effects and,-therefore, by the statement of the specification'and claims that the steam temperature is set or reduced to substantially a constant figure, it is to be understood that the temperature is kept constant within a certain amount of permissible variation, and is not to be taken as absolutely constant.

In the preferred form as it has been described a volatile liquid is used in the closed vessel or evaporator-1O Instead of-a Volatile liquid, air or othergas', or a liquid which would not be volatile at the temperature involved could be used. However, I prefer a volatile liquid for the reason that any distortion that might change the volume of the.

evaporatonlO, or any slight leakage in the evaporator, or in the plpes, will not affect the result obtainedprovided sufficient of the liquid remains in the evaporator; whereas, the result would be afiected through such causes if other than a volatile liquid were used.

The foregoing examples of apparatus by which my method of temperaturerontrol may be practised comprise as an essential volatile liquid. In Figs. .14 and 15 I have shown the application of a thermostatic device depending upon the unequal expansion of different metals to control the position of valve or cock 9. The attemperator, and the regulator of the Carmichael or Spencer type are the same as heretofore described. Instead, however, of a closed evaporator in the pipe section {1; of the controller, I place therein a thermostat consisting of a tube closed at its lower end by a cap 76 and secured at its upper end to a cap piece 77.

. Resting within the tube upon its cap 7 6 is a of iron or steel and the tube 75 of some metal having a greater coeflicient of expansion than the bar or tube 78, preferably of aluminum. As will be obvious, the expansion and contraction of the tube 75 and bar 78 due to minute differences in temperature of the steam leaving the attemperator will effect a movement of lever 17,- and this force will call into play a device driven by supplemental energy to control the position of the valve vor cock 9 and consequently the volume of water admitted :.to the attemperator, in precisely the same manner as such control is effected by the pressure generated in the evaporator 10. As the tube 75,.can expand only in a downward direction, and having a greater coeflicient of expansion than the tube or bar 78, any excess of steam temperature above the constant will result in lowering lever 17 to open the valve or cock 9 to admit a volume of Water proportionally greater than that required to maintain the normal steam temperature. If the steam temperature falls below the normal the more rapid contraction of tube 75 will raise lever 17 to decrease the volume of water admitted to the attemperator.

Fig. 16 shows substantially the same arrangement as is shown in Fig. 13 except for the substitution for the closed evaporator of the thermostat shown in Fig. 14. In such element, however, the tube 75, as before stated, has a sufficiently greater coefficient of expansion than the bar or tube 78 to impart the desired movement to lever 79 which is in the form of a contact finger adapted to close circuit 35 througheither of the contacts 3637. When the circuit 35 is closed, the corresponding magnet 3637 will be energized to thereby close the motor circuit 38 to rotate the motor 33 in one direction or the other as fully described in connection with Fig. 13.

Any one of the thermostats described by me as available to call into play a device driven by supplemental energy to determine or control the position of the cock 9 may be ature of superheated steam which consists in subjecting the steam to the action of a cooling medium to reduce the temperature to a predetermined constant,-and then causing any varlation from that constant to efdetermined constant and utilizing any variation from that constant to vary the amount of water to restore the steam temperature to substantially that of the constant.

3. The method of regulating the temperature of superheated steam which consists in subjecting superheated steam of a varying initial temperature to the action of a cooling medium to reduce the steam temperature to a predetermined constant, then passing the steam, after its temperature has been reduced, into contact with a closed evaporator containing a vvolatile liquid whereby any variation of the temperature of the steam will produce a corresponding variation in the temperature of the volatile liquid and the pressure of its vapor, and utilizing such vapor pressure to admit a greater or less quantity of the cooling medium to the initial steam, as the steam surrounding the evaporator varies above or below the predetermined constant. a

4. The method of regulating the temperature of superheated steam which consists in admitting a-regulated quantity of water to superheated steam of a varying initial tem-' 'perature to reduce the steam temperature to a predetermined constant, then passing such steam into contact with a closed evaporator containing a volatile liquid whereby any variation of the temperature of the steam will produce a corresponding variation in the temperature of the volatile liquid and the pressure of its'vapor, and utilizing such vapor pressure toact upon a regulator to admita greater or less quantity of water to the steam of varying initial temperature as the steam surrounding the evaporator vanes above or below the predetermined constant.

5. The method of regulating the temperature of superheated steam which consists in subjecting the steam to the actionof a cooling medium to reduce the temperature to' a predetermined constant, then passing the steam into contact with a thermostat and constant to vary the amount of the cooli g medium to restore the steam temperature to substantially that of the constant.

6. The method of regulating the temperature of superheated steam which consists in subjecting superheated steam of a varying initial temperature to the action of a cooling subjecting-the steam ture of superheated determined constant.

temperature of the .medium to reduce the steam temperature to a predetermined constant, then passing such steam 'into contact with a closed evaporator containing a volatile liquid whereby any variation of the temperature of the steam will produce a corresponding variation in the'temperature' of the volatile liquid and the pressure of its vapor, and utilizing such vapor pressure to close a circuit to thereby admit a greater or less quantity of the cooling medium to the, initial steam as the steam surrounding the evaporator varies above or below the predetermined constant.

7. The method of regulating the tempera ture of superheated steam which consists in to the action of a coolmedium to reducethe temperature to a predetermined constant, and then causing i any variation from that constant to act upon and control a source of supplemental energy to eitect a corresponding variation in the volume of the cooling medium to thereby restore the steam temperature to substantially that of the constant.

8. The method of regulating the temperasteam which consists in admitting a regulated quantity of a cooling medium to reduce the steam temperature to a predetermined constant, then passing the steam after its temperature has been reduced 95 into contact with a thermostat whereby any variation of the temperature of the steam will correspondingly act upon the thermostat, and utilizing the movements of the thermostat to control a source of supplemental energy to thereby admit a greater or less quantity of the coolingmedium to the initial steam as the steam surrounding the thermostat varies above or below the preing 9. The method of regulating the temperature of superheated steam which consists in subjecting superheated steam of a varying initial temperature to the action of a cooling medium to reduce the steam temperature to 1 a predetermined constant, then passing the steam after its temperature has been reduced, into contact with a closedevaporator containing a volatile liquid whereby any variation of the temperature of the steam will produce a corresponding variation in the volatile liquid and the pressure of its vapor, and utilizing such vapor pressure to control a source of supplemental energy which acts to admit a greater or less quantity of the cooling medium to the initial steam as the steam surrounding the evaporator varies above or below the predetermined constant.

10. In combination, an attemperator to 135 which steam of a varying initial temperature is admitted, means for admitting a cooling medium to the attemperator to re-' duce the temperature of the steam to a predetermined constant, a thermostat and" temperature has been modified, into contact with said thermostat, and means controlled by said thermostat to effect a corresponding variation in the volume of thecooling medium to thereby restore the steam temperature to substantially that of the constant.

11. In combination, an attemperator to which steam of a varying initial temperature is admitted, means for admitting a cooling medium to the attemperator to reduce the temperature of the steam to a predeterminedconstant, a thermostat andmeans for conducting the steam, after its temperature has been modified, into contact with said thermostat, mechanism, to govern the supply of said medium comprising a source of supplemental energy. and means controlling said, source of energy operated by said thermostat to effecta corresponding variation in the volume of the cooling medium to thereby restore the steam temperature to substantially that of the constant. H

12. In combination, an attemperator to which steam of a varying initial tempera ture is admitted, means for admitting a cooling medium to the attemperator to reduce the temperature of the steam to a predetermined constant, a closed evaporator containing a volatile liquid placed in the path of the steam after'it leaves the attemperator, mechanism,to governthe supply of said medium comprising a source of supplemental energy, and means controlling said source of energy operated by the slight differences of pressure which are produced in the evaporator by the temperature variations in the steam surrounding the evaporator to effect a corresponding variation 1n the volume of the cooling medium to thereby restore the .steam temperature to substantially that of the constant.

In testimony whereof I have hereunto signed my name in the presence of tWo subscribing Witnesses. v

' DAVID S. JACOBUS. Witnesses:

CHARLES, S. JoNEs, Loms J. BERNSTEIN. 

